Decoder" Program Step - Siemens SIMATIC MV500 Operating Manual

5.1.4

"Decoder" program step

You define the following settings in this program step:
● The decoding method you work with.
● The code types that are read.
● The format in which the read result is output.
● The decoder type you are using.
● The criteria by which the comparison with a specification was successful.
● The conditions under which the code did not meet the quality expectations, and the
overall result of the program may be "N_OK".
● You limit the Region of Interest (ROI) in the image display: Pull the rectangle with the
mouse.
– Whether the ROI follows the result of a preceding step.
– Whether one or more codes are read in the ROI.
Note
Multicode
• Cell size of the codes must not vary greatly
For successful processing, the cell size of the codes that occur must not vary greatly
when using the "Multicode" option.
• Polarity must be uniform
Several barcodes, including barcodes of different types, can be decoded in a single step.
However, this only works when all barcodes have the same polarity (black on white or
white on black). Barcodes of mixed polarity can be read in a program using two "Read
code" steps.
Note
ROI position
• "Follow x" is not executed with enabled formation of result
When formation of result is enabled, the "Follow x" function is not executed. The ROI
positions remain fixed in this mode.
• "Follow step x" functions only for a unique result position of the reference
The step serving as reference for the ROI position must generate a unique result position
for error-free functioning.
If the reference step processes multiple codes or object instances, a unique result
position is not generated. In this case, the instance or the code with the poorest quality
serves as the reference position. Error-free functioning is not ensured.
SIMATIC MV500
Operating Manual, 05/2019, C79000-G8976-C495-02
Application
5.1 Program
39